1. Technical Field
The present invention relates to a joint drive type link mechanism equipped with a link including a joint portion in the intermediary thereof and a driving source for driving the joint portion, and a walking assist device (walking auxiliary equipment) using the link mechanism.
2. Description of the Related Art
Conventionally, there has been known a walking assist device configured from a load transmitting portion, a foot attachment portion to be attached to a foot of a user, and a leg link mechanism provided between the load transmitting portion and the foot attachment portion (for example, refer to Japanese Patent Laid-open No. 2007-20909). In this type of the walking assist device, the leg link mechanism is configured from a joint drive type link mechanism equipped with a leg link including a joint portion in the intermediary thereof and a driving source comprised of an electric motor for driving the joint portion. By driving the joint portion with the driving source, the leg link is actuated in the direction of pushing up the load transmitting portion, so as to support at least a part of a body weight of the user by the leg link via the load transmitting portion.
In the conventional walking assist device mentioned above, an electric component such as a motor driver for use in controlling the driving source is accommodated in a backpack to be worn by a user. However, this makes the user suffer a burden. Therefore, it is desired that the electric component be mounted on the device side in order to reduce the burden of the user.
Here, there has been known a type in which the electric component for use in controlling the driving source for driving the joint is mounted to the link of the joint drive type link mechanism constituting a leg of a walking robot (for example, refer to Japanese Patent Laid-open No. H5-237775). It is conceivable to apply this technology to the leg link mechanism of the above-mentioned walking assist device, and mount the driving source for driving the joint as well as the electric component for use in controlling the driving source to the leg link. In this case, however, there arise inconveniences as listed below. That is, when the electric component is mounted to the leg link, the temperature of the leg link increases by the heat of the electric component due to power distribution. In the walking assist device, the leg link is arranged in the vicinity of the leg of the user, so that the user may feel uncomfortable from the heat affection reaching the leg of the user due to increase in temperature of the leg link.